1. Field of the Invention
The present teaching relates to a surface inspection apparatus and a surface inspection method for inspecting substrate surfaces having a predetermined pattern. Further, the present teaching relates to an exposure system including such surface inspection apparatus and an exposure device, and a method for producing a semiconductor device utilizing such surface inspection method.
2. Description of the Related Art
Exposure devices of step-and-scan type carry out exposure on one shot for a semiconductor wafer by relatively moving a reticle stage (i.e. a mask substrate with a mask pattern formed therein) and a wafer stage (i.e. a wafer on which a semiconductor pattern is to be formed) to scan just one shot while irradiating with a slit-shaped Light beam via the mask pattern and a projection lens. In so doing, because the size of an exposure shot is determined by the relative distance of scanning between the long side or the slit (light) and the reticle stage, it is possible to enlarge the exposure shot.
For such kind of exposure devices, a focus control (a control of the focusing state of the pattern on the wafer surface) is important. Therefore, the focusing state of the exposure device on the wafer surface is monitored (here, the focusing control is not limited to problems due to defocusing, but refers to the control of variation of the focusing state within a shot or on the entire wafer surface). In order to measure the focusing state of the exposure device, for example, there are methods predetermined as utilize a dedicated mask substrate to expose and develop a test pattern, and measure a focus offset from positional deviation of the obtained test pattern (for example, see Japanese Patent Application Laid-Open No. 2002-289503).